1. Field of the Invention
The present invention relates to methods for disinfecting articles, and, more particularly, to a method of disinfecting both the articles and an inner vessel.
2. Description of the Prior Art
There are currently no automated systems available for consistently providing completely disinfected medical instruments after rinsing. The conventional automated systems are often adequate for disinfecting the instruments during the initial wash or disinfect cycle but fail to maintain the instruments in a disinfected state following the rinsing cycle.
U.S. Pat. No. 3,893,843 discloses an automated system for disinfecting inhalation therapy and anesthesia items which cannot be subjected to high heat. Contamination by waterborne microorganisms during and following the rinsing cycle was evidently not a concern and is not addressed.
Waterborne microorganisms are of great concern as a source of contamination during the processing of instruments. Droplets of liquid from surfaces on those portions of the system which are not part of the disinfected field (have not been in continuous contact with a disinfectant) can fall on the disinfected instruments when lids are opened or when trays are jostled and the instruments removed, thereby contaminating the instruments. Of prime concern for purposes of the present invention is the potential for such droplets to contaminate disinfected instruments. Airborne microorganisms which present problems after processing, during drying and storing are not addressed in the present invention.
Manual methods of disinfecting medical instruments involve rinsing the instruments, washing in soapy water in a basin, soaking with 2% gluteraldehyde or a similar disinfectant, and rinsing with sterile water. A thorough rinse with sterile water for typical medical instruments such as endoscopes, may require approximately two liters of presterilized water. The manual method may yield completely disinfected instruments with greater consistency than the conventional automated methods but requires more counterspace and ancillary instruments, and is more labor intensive.
Osuch U.S. Pat. No. 2,246,104, which issued on June 17, 1941; Sacks et al. U.S. Pat. No. 2,743,733, which issued on May 1, 1956; Wanzer U.S. Pat. No. 2,788,008, which issued on April 9, 1957; and Faust et al. U.S. Pat. No. 3,590,683, which issued on July 6, 1971 disclose the use of various apparatus, each of which includes an inner vessel disposed within an outer vessel. The apparatuses and methods provided by those patents do not provide a means or method for consistently yielding completely disinfected instruments from an automated system following the rinsing cycle. The potential for droplet contamination is not addressed.
Accordingly, there is a need for a method for disinfecting medical instruments which will maintain the instruments in a disinfected state during and following the rinsing cycle. There is a further need for a method of disinfecting medical instruments which will eliminate the possibility of contaminated droplets entering the disinfected field following the disinfection of the instruments.